If one were to make a choice of going on foot while other people had the privilege of wings, he would be haunted by the fear that he had made a mistake, and as he trudged along in the mire, doubtless would envy the people in the air above him; but if he had no choice in the matter and was compelled to go afoot through no fault of his, he would thank his stars that his fate was no worse. When choice comes in and we can elect this or that, then the door for regret, for unhappiness, is opened. We do not mourn because we were born in this place and not that, but if we had been consulted we might fancy some cause of regret. Yet there is a condition or circumstance that has a greater bearing upon the happiness of life than any other. What is it? I have hardly hinted at it in the foregoing remarks. It is one of the simplest things in the world and within reach of all. If this secret were something I could put up at auction, what a throng of bidders I should have, and what high ones! People would come from all parts of the earth to bid upon it. Only the wise ones can guess what it is. Some might say it is health, or money, or friends, or this or that possession, but you may have all these things and not be happy. You may have fame and power, and not be happy. I maintain there is one thing more necessary to a happy life than any other, though health and money and friends and home are all important. That one thing is--what? The sick man will say health; the poor man, wealth; the ambitious man, power; the scholar, knowledge; the overworked man, rest. Without the one thing I have in mind, none of these things would long help their possessors to be happy. We could not long be happy without food or drink or clothes or shelter, but we may have all these things to perfection and still want the prime condition of happiness. It is often said that a contented mind is the first condition of happiness, but what is the first condition of a contented mind? You will be disappointed when I tell you what this all-important thing is,--it is so common, so near at hand, and so many people have so much of it and yet are not happy. They have too much of it, or else the kind that is not best suited to them. What is the best thing for a stream? It is to keep moving. If it stops, it stagnates. So the best thing for a man is that which keeps the currents going,--the physical, the moral, and the intellectual currents. Hence the secret of happiness is--something to do; some congenial work. Take away the occupation of all men, and what a wretched world it would be! Half of it would commit suicide in less than ten days.